Issue with using oci_load and external dependencies

[theunwisewolf]

I have 2 bazel modules. One at the root and the other in a sub directory. Example:

root
  /libA
    /BUILD.bazel <-- uses oci_load()
    /MODULE.bazel
  MODULE.bazel <-- Imports libA's module

In the root MODULE.bazel I have:

bazel_dep(name = "libA", version = "1.0")
local_path_override(module_name = "libA", path = "./libA")

And libA's BUILD file has:

... build app, package to tar, transition binary

oci_load(
    name = "load",
    image = ":transitioned_image",
    repo_tags = "tags.txt",
)

When I run bazel run @libA//:load, the command fails with the error:

tar: Error reading archive -: Can't open external/libA+/image/blobs/sha256/d057aa77ea6c6e060f84c1bbe1a261478509b8d0f11bdbbd3ca6a5a3bbd1e2d0
tar: Error exit delayed from previous errors.
open /var/lib/docker/tmp/docker-import-1307345443/repositories: no such file or directory

If I run bazel run //:load inside libA dir, it runs fine. I can also run the app from the root directory without any issues. It's only the image creation that fails.
I suspect the '+' symbol in the name is causing some problems for the tar command.

So the oci_load() does not work when used with external dependencies. Any workarounds/fixes?

[sfc-gh-mhazy]

I am running into the same issues, I think the problem is with load implementation and path remapping.

I believe in

rules_oci/oci/private/load.bzl

Line 220 in 843eb01

"{{manifest_root}}": manifest_json.root.path,

: manifest_root, image_root and workspace_name are not working with running oci_load defined in different module / repository.

Suppose we have a workspace / module named "main" and it imports "other" that has @other//path:my_oci_load

The following are the problems:

1. ctx.workspace_name seems to always returns the name of "main" workspace. But we would want "other"
2. file.root.path returns the root of all outputs - lets say "/path/to/my/root"
   • But whole path of file from @other//path:target is /path/to/my/root/external/other/path/target. For targets in "main" it would be /path/to/my/root/main/path/target (No external prefix)

In the end, the load executable would not strip enough from the path and then go into wrong directory ($RUNFILES_DIR/main, while it should go to $RUNFILES_DIR/other)

I am not sure what is the best solution here, but I generally tend to use file.short_path to distinguish between these two cases (if short path starts with .. -> this is external repository and next directory is a workspace name. Not sure if this is the "clean" solution though.

Roughly:

def _get_workspace(ctx, file):
    if file.short_path.startswith("../"):
        short_path = file.short_path
        split = short_path.split("/")
        return split[1]
    return ctx.workspace_name

def _get_prefix_to_trim(ctx, file):
    workspace = _get_workspace(ctx, file)
    if workspace != ctx.workspace_name:
        return file.root.path + "/external/" + workspace
    return file.root.path